package cn.sns.sample;

import java.util.*;
import java.util.regex.*;

/**
 * This program tests regular expression matching. Enter a pattern and strings
 * to match, or hit Cancel to exit. If the pattern contains groups, the group
 * boundaries are displayed in the match.
 */
public class RegExTest {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		System.out.println("Enter pattern: ");
		String patternString = in.nextLine();

		Pattern pattern = null;
		try {
			pattern = Pattern.compile(patternString);
		} catch (PatternSyntaxException e) {
			System.out.println("Pattern syntax error");
			System.exit(1);
		}

		while (true) {
			System.out.println("Enter string to match: ");
			String input = in.nextLine();
			if (input == null || input.equals(""))
				return;
			Matcher matcher = pattern.matcher(input);
			if (matcher.matches()) {
				System.out.println("Match");
				int g = matcher.groupCount();
				if (g > 0) {
					for (int i = 0; i < input.length(); i++) {
						for (int j = 1; j <= g; j++)
							if (i == matcher.start(j))
								System.out.print('(');
						System.out.print(input.charAt(i));
						for (int j = 1; j <= g; j++)
							if (i + 1 == matcher.end(j))
								System.out.print(')');
					}
					System.out.println();
				}
			} else
				System.out.println("No match");
		}
	}
}